Pressurized-gas powered compressor and system comprising same

ABSTRACT

The present invention provides a compressor powered by a pressurized gas, whether steam or another working fluid, and a system for extracting work using such as compressor. The pressurized gas may comprise a heated working fluid in a gaseous state, to displace a piston in an input circuit, which in turn displaces a piston in an output circuit, thereby compressing a compressible fluid or displacing an incompressible fluid. A purpose of the compressor is to convert waste heat, heat generated by the combustion of biomass or other fuels, or heat resulting from the concentration of solar energy into useful power, whether configured to produce compressed air or pump water, which can displace the electricity otherwise used for this purpose, or to produce electricity or motive force directly, through a hydraulic circuit. The system for extracting work does so by an output fluid which is compressed or pumped by a pressurized gas powered compressor.

FIELD OF THE INVENTION

The present invention pertains in general to the field ofpressurized-gas powered equipment, such as steam-powered equipment andmore specifically a pressurized gas powered compressor and a system forextracting work using same.

BACKGROUND

Heat engines, such as steam engines, have long been used for convertingheat energy into mechanical output. For example, Worthington steampumping engines, for example as described in The Worthington SteamPumping Engine: History of its Invention and Development,” by H. R.Worthington, New York, 1887, may utilize a steam-driven piston forpumping water. Other reciprocating engines are also known for producingpumping action of pistons using steam power, for example as described in“Practical Handbook on Direct-Acting Pumping Engine and Steam PumpConstruction,” by P. R. Bjorling, London and New York, 1889. Such pumpstypically pump water via pumping action of a piston by pushing water outof a cylinder, the piston driven by a steam-driven piston. However,reciprocating steam pumps based on these designs are often heavy,inefficient and costly, and ill adapted for performing forms of workother than the pumping of liquids.

Another type of steam engine is a steam-driven turbine, which may beused for extracting power from superheated steam. However, turbinestypically require dry, and generally superheated steam, provided to theturbine under precisely controlled conditions. These constraints limittheir usefulness, for example in systems where only wet saturated steamis available, or where the steam supply is irregular.

A number of other steam engines have been developed in recent years,which attempt to efficiently generate rotary motion from wet saturatedsteam. However, many of these are not well adapted to the production ofelectricity, given the torque and rotational speeds required of agenerator for efficient electricity generation.

The uses of low and medium pressure saturated steam are largely limitedto space and water heating. These uses fail to exploit the fullpotential of such steam for producing useful power. For example,residual heat from industrial processes is typically used for heatingpurposes, rather than for providing mechanical or electrical power.

Therefore there is a need for a new device and system that can extractdesired useful work from pressurized gas such as wet saturated steam.

A number of systems have also been developed in recent years composed ofturbines driven by the vapour of a low-boiling point (LBP) working fluid(“Organic Rankine cycle turbines”). These systems are capable ofextracting useful work from a heat source of relatively low temperature.However, they are subject to the same constraints as other turbines, andas a result their capital and operating costs are often too high formany applications.

There is thus also a need for a new device and system that can extractuseful work from relatively low-temperature heat sources, without thecosts and operational constraints associated with Organic Rankine Cycleturbines.

This background information is provided to reveal information believedby the applicant to be of possible relevance to the present invention.No admission is necessarily intended, nor should be construed, that anyof the preceding information constitutes prior art against the presentinvention.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a pressurized gaspowered compressor and a system comprising same. In accordance with anaspect of the present invention, there is provided a system forextracting work using a pressurized gas powered compressor, the systemcomprising: a compressor powered by a pressurized gas, the compressorcomprising an output circuit configured to operate compressively on anoutput fluid supplied thereto; a pressurized gas input system configuredto provide the pressurized gas for powering the compressor; an exhaustsystem configured to convey spent gas from the compressor; and a workextraction system configured to extract work from the compressor atleast in part via said output fluid.

In accordance with another aspect of the present invention, there isprovided a compressor powered by a pressurized gas, comprising: an inputcircuit configured to channel the pressurized gas through two or moreinput piston-cylinder assemblies, wherein each input piston-cylinderassembly is configured to expel spent gas after use; an output circuitincluding two or more output piston-cylinder assemblies, each outputpiston-cylinder assembly including an intake valve for entry of fluidand an output valve for exit of compressed fluid; a transfer systemconfigured to transfer force generated in the input piston-cylinderassemblies onto the output piston-cylinder assemblies; a return systemconfigured to facilitate a return stroke of at least a first one of theinput piston-cylinder assemblies following a power stroke thereof; atiming system configured to control input and exhaust of the pressurizedgas from the input piston-cylinder assemblies; and a distribution systemoperatively coupled to the timing system, to the pressurized inputsystem, and to the input circuit, the distribution system configured tocooperatively provide pressurized gas to the input piston-cylinderassemblies.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 illustrates a cross-section of a pressurized gas poweredcompressor according to one embodiment of the present invention.

FIG. 2 illustrates an isometric cross-section of a piston of thepressurized gas powered compressor of FIG. 1, in accordance with anembodiment of the present invention.

FIG. 3 illustrates a cross-section of an output cylinder fitted with anintegrated bidirectional check valve in accordance with an embodiment ofthe present invention.

FIG. 4 illustrates an isometric cross-section of a timing system,composed of a crankshaft, gearbox and related elements of thepressurized gas powered compressor of FIG. 1, in accordance with anembodiment of the present invention.

FIG. 5 illustrates a detailed, partially exploded, isometric view of thevalve body of the distribution system of the pressurized gas poweredcompressor of FIG. 1, in accordance with an embodiment of the presentinvention.

FIG. 6 illustrates a view of the assembled valve body and valve bodyhousing of the distribution system of a pressurized gas poweredcompressor, in accordance with an embodiment of the present invention.

FIG. 7 illustrates a secondary sealing assembly of the valve bodyhousing of the distribution system of a pressurized gas poweredcompressor, in accordance with an embodiment of the present invention.

FIG. 8 illustrates a system for extracting work from pressurized gas,using a pressurized gas powered compressor, in accordance withembodiments of the present invention.

FIG. 9A illustrates a configuration for driving a pressurized gaspowered compressor using residual steam, in accordance with anembodiment of the present invention.

FIG. 9B illustrates a configuration for driving a pressurized gaspowered compressor using steam generated using one or more heat sources,in accordance with an embodiment of the present invention.

FIG. 10A illustrates a configuration for producing compressed air usinga pressurized gas powered compressor, in accordance with an embodimentof the present invention.

FIG. 10B illustrates a configuration for producing motive force using apressurized gas powered compressor, in accordance with an embodiment ofthe present invention.

FIG. 10C illustrates a configuration for producing electricity using apressurized gas powered compressor, in accordance with an embodiment ofthe present invention.

FIG. 11 illustrates a system for producing electricity from solar energyusing a pressurized gas powered compressor, in accordance with anembodiment of the present invention.

FIG. 12 illustrates a system for extracting electricity from biomasscombustion using a pressurized gas powered compressor, in accordancewith an embodiment of the present invention.

FIG. 13 illustrates a system for extracting electricity from solarenergy, biomass combustion, or a combination thereof, using apressurized gas powered compressor, in accordance with an embodiment ofthe present invention.

FIG. 14 illustrates a system for extracting electricity from anindustrial heat source using a pressurized gas powered compressor, inaccordance with an embodiment of the present invention.

FIG. 15 illustrates a system for extracting motive force from anindustrial heat source using a pressurized gas powered compressor, inaccordance with an embodiment of the present invention.

FIG. 16 illustrates a system for producing compressed air from residualsteam using a pressurized gas powered compressor, in accordance with anembodiment of the present invention.

FIG. 17 illustrates a system for pumping water using solar energy usinga pressurized gas powered compressor, in accordance with an embodimentof the present invention.

FIG. 18 illustrates a pressurized gas powered compressor having fourpiston-cylinder assemblies, in accordance with an embodiment of thepresent invention.

FIG. 19 illustrates a piston-cylinder assembly having its axis offsetfrom the axis of a crankshaft, in accordance with an embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION Definitions

The term “pressurized gas” is used to define a gas with a pressuregreater than atmospheric pressure, which may or may not be latercondensed to a liquid state.

The term “spent gas” is used to define a pressurized gas which has lostsome or all or its pressure, and which may or may not have partiallyconverted to a liquid state.

The term “condensate” is used to define a portion of spent gas which hasconverted to a liquid state.

The term “working fluid” is used to define a fluid that, when heated,converts from a liquid to a gaseous state, and which when in a gaseousstate may exert pressure upon a piston within a cylinder.

The term “compression” is used to define the application of pressure toa fluid. In the case of a compressible fluid such as air, this pressureresults in compression, as commonly understood. In the case of anincompressible fluid, such as hydraulic fluid, it results in thedisplacement of said fluid within a confined channel, such as ahydraulic circuit.

The term “compressed fluid” is used to define a compressible orincompressible fluid upon which pressure has been exerted by a pistonwithin a cylinder.

As used herein, the term “about” refers to a +/−10% variation from thenominal value. It is to be understood that such a variation is alwaysincluded in a given value provided herein, whether or not it isspecifically referred to.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs.

Aspects of the present invention provides a device which uses thepressure of a pressurized gas, which may comprise a heated working fluidin a gaseous state, to displace a piston in an input circuit, which inturn displaces a piston in an output circuit, thereby compressing acompressible fluid or displacing an incompressible fluid.

Aspects of the present invention provide a compressor powered by apressurized gas. The compressor comprises an input circuit configured tochannel the pressurized gas through two or more input piston-cylinderassemblies, wherein each input piston-cylinder assembly is configured toexpel spent gas after use. The compressor further comprises an outputcircuit including two or more output piston-cylinder assemblies, eachincluding an intake valve and an output valve allowing the exit ofcompressed fluid. In some embodiments, a dimension ratio between theinput piston-cylinder assemblies and the output piston-cylinderassemblies is selected to provide a desired pressure on a recipientfluid in the output piston-cylinder assemblies. The compressor furthercomprises a return system configured to return pistons to their startingpositions following a power stroke. For example, each input piston maybe returned to a starting position by action of the return system. Thereturn system may also be configured to return output pistons to theirstarting positions. For example, the return system may be configured toreturn an input piston and an output piston to their correspondingstarting positions, wherein the input piston and output piston arecoupled together, for example via a transfer system. The compressorfurther comprises a transfer system configured to transfer forcegenerated in the input piston-cylinder assembling onto the outputpiston-cylinder assemblies, and a timing system configured to controlinput and exhaust of the pressurized gas from the input piston-cylinderassemblies. The compressor further comprises a distribution systemoperatively coupled to the timing system, a pressurized gas reservoirand the input piston-cylinder assemblies, the distribution systemconfigured to cooperatively provide pressurized gas to the inputpiston-cylinder assemblies.

In some embodiments, the pressure in the output circuit depends at leastin part on the pressure of the pressurized gas and the ratio between thesquare of the diameters of the input and output cylinders, minusfrictional losses. The output pressure can be equal to, less than orgreater than the pressure of the pressurized gas, depending on therelative diameters of the input and output cylinders.

In some embodiments, the pressurized gas powered compressor is operatedin a horizontal position with a slight incline allowing condensate to beexpelled from the input cylinders through a steam trap at the end ofeach return stroke.

According to embodiments of the present invention, an application of apressurized gas powered compressor is to produce compressed air by themeans of steam or another pressurized vapour or gas. This pressurizedvapour or gas can consist of residual low-grade steam or can begenerated at least in part using heat from a variety of heat sources,including, waste heat, biomass combustion, solar concentrators, etc.

According to embodiments of the invention, an application of apressurized gas powered compressor is to facilitate conversion ofindustrial waste heat, for example as conveyed by low-grade steam, intouseful power, for example by using the energy contained in steam tobuild pressure in a compressed air tank. Stored compressed air may beutilized for example for supplying industrial compressed air systems.Moreover, in some embodiments, the extraction of useful work form lowgrade steam flows can allow the displacement of electrical load fromexisting compressors, which may increase the plant's energy efficiencyand lower energy costs. In some embodiments, exhaust from thepressurized gas powered compressor may be used for heating or otherpurposes. Low grade steam is generally used for heating purposes, butits prior use in a compressor configured in accordance with embodimentsof the present invention, may reduce its heating value only slightly, asthe latent heat is typically only released when the steam is condensedto water in a heat exchanger or a condenser.

In accordance with embodiments of the present invention, the pressurizedgas powered compressor may be configured for providing a low-costsolution for converting heat to electricity or other useful forms ofpower, whether through a hydraulic circuit or by other means.Furthermore, embodiments of the compressor of the present invention canhave a compact and modular arrangement which can make it adaptable for avariety of applications, and additionally, its simplicity can keepmaintenance costs low.

Aspects of the present invention provide a system for extracting workusing a pressurized gas powered compressor. The system comprises apressurized gas powered compressor, the pressurized gas poweredcompressor comprising an output circuit configured to operatecompressively on an output fluid supplied thereto. The system furthercomprises a pressurized gas input system configured to providepressurized gas for powering the pressurized gas powered compressor. Thesystem further comprises an exhaust system configured to convey spentgas from the pressurized gas powered compressor. The system furthercomprises a work extraction system configured to extract work from thepressurized gas powered compressor at least in part via said outputfluid.

An embodiment of a pressurized gas-powered compressor in accordance withan aspect of the present invention is illustrated in FIG. 1. Thecompressor comprises two or more input piston-cylinder assembliesmounted on one side of a frame (51), a similar number of outputpiston-cylinder assemblies mounted on the other side of the same frame(51), transfer rods (15) connecting each input piston assembly with acorresponding output piston assembly, a return system configured toreturn each piston to its starting position following its power stroke,a distribution system (23) which connects the input cylindersalternately to a source of pressurized gas and to an exhaust system, forexample for venting spent gas to the atmosphere or to a low-pressurereservoir (not shown), or the like, and a timing system configured tofacilitate synchronisation of operation of the distribution system andthe input piston-cylinder assemblies, for example by timing intake andexhaust of working fluid thereby. Each of these assemblies is describedbelow.

Piston-Cylinder Assemblies

Having particular regard to the embodiment illustrated in FIG. 1, when apressurized gas is allowed into an interior cavity of an input cylinder(19) by the distribution system (23), it exerts pressure on acorresponding input piston (18) slideably mounted in the input cylinder(19), thereby tending to put the piston into motion. The input piston inturn exerts pressure on the piston base (14), to which it is linkedmechanically via transfer rods (15) as described below, which in turnexerts pressure on the output piston (10), to which it is linkedmechanically via a rod end (11) and shaft (12), described below. Theoutput piston in turn exerts pressure on a compressible orincompressible fluid contained in the output cylinder (8), creatingpressure. The fluid contained in the output cylinder (8) may then bechannelled under pressure to perform work, store energy, or the like.For example, the fluid may be channelled through a check valve (4) andthence to a reservoir or work extraction system or other machinery orequipment.

Each input cylinder-piston assembly comprises a hollow input cylinder(19), a cylinder head (22), and a piston (18) slidingly engaging theinterior walls of the cylinder (19) and forming a seal therewith. Theinput cylinder-piston assembly may further comprise one or more sealingrings (24) for each piston. The cylinder head (22) may comprise arounded cap (20) fixed to the cylinder by mechanical means, such asbolted joints. The cap (20) may include a port (21) allowing connectionbetween the interior of the cylinder and the distribution system as wellas a steam trap (not shown) for evacuating condensate.

In some embodiments, the flow of pressurized gas into an input cylindercorresponds to a power stroke for said cylinder, wherein the pressurizedgas tends to expand the volume of a cylinder cavity, substantiallydefined by interior walls of the cylinder (19), the cylinder head (22)and the piston (18), by motion of the piston. The power stroke istypically followed by a return stroke, wherein the volume of thecylinder cavity contracts, by motion of the piston, and the pressurizedgas within the cylinder cavity is outlet via an output port.

The sealing ring assemblies (24), which in some embodiments canfacilitate operation of the piston-cylinder assembly without applicationof a lubricating film, are illustrated in more detail in FIG. 2. Eachsealing ring assembly (24) may comprise an O-ring (26) set into a deepgroove (27) machined into the piston, which applies outward pressure toa cylindrical ring (28) made of a low-friction material such asvitrified PTFE. This cylindrical ring, which in some embodiments ismachined on its inner surface to form a groove into which the O-ringfits, sits in a wider and shallower groove machined into the piston.

As further illustrated in FIG. 1, each output cylinder-piston assemblymay comprise a cylinder head (7), a cylinder (8), a cylinder flange (57)fixed to a spacer flange (58), a piston (10), a piston base (14), aspacer (13), a rod end (11) on a shaft (12), such as a threaded shaft,and one or more sealing ring assemblies (9) similar to those of theinput pistons. In some embodiments, at least one of these sealing ringassemblies (9) may be replaced with a profiled rod/piston seal made ofnitrile or other flexible material. The piston base is connected to theinput piston by rods (15). The output cylinder head (7) comprises a cap(5) affixed to the cylinder by mechanical means, such as bolted joints.The output cylinder head (7) includes an output port (4) fitted with acheck valve, and an air intake port equipped with another check valve(not shown). The input port may be operatively coupled to a source offluid, such as a hydraulic circuit, air intake, or the like. The outputport may be operatively coupled to a reservoir system, storage device,hydraulic circuit, hydraulic or hydro-pneumatic accumulator, hydraulicmotor, or the like. Fluid conveyed by the output port may thereby beharnessed to perform useful work, for example.

In some embodiments, one or more check valves, operatively coupled to anoutput cylinder, may be replaced with an integrated bidirectional checkvalve, as illustrated in FIG. 3. The illustrated integratedbidirectional check valve comprises an inner flange (49) and an externalflange (50), the inner flange (49) slideably coupled over the outputcylinder (8), and the external flange (50) slideably coupled over theinner flange (49). The integrated bidirectional check valve mayfacilitate substantially unimpeded filling and for emptying of outputcylinder (8) by a system of holes or apertures, for example when theoutput cylinder (8) is surrounded by a fluid, such as ambient air orwater. The integrated bidirectional check valve may also facilitateexpulsion of pressurized fluid from the output cylinder, withsubstantial reduction or elimination of “dead space” that results fromthe use of traditional check valves.

The integrated bidirectional check valve illustrated in FIG. 3 isdescribed as follows. The inner flange (49) is fitted overtop of theoutput cylinder (8) and slideably engaged therewith. The external flange(50) is fitted overtop of the inner flange (49) and slideably engagedtherewith. The inner flange (49) comprises one or more holes (51) in aside thereof, such that the holes (51) are configured to align tosimilar holes (52) in the output cylinder (8) when the inner flange isslideably moved into a retracted position. When aligned, holes (51) andholes (52) form a channel facilitating communication between theinterior portion of the cylinder (8) and the external environment,thereby facilitating filling of the cylinder (8) with fluid during areturn stroke, the fluid to be compressed during a subsequent powerstroke.

In some embodiments, the inner flange (49) may be slideably supported byrods (not shown) attached to the cylinder flange (57), furthersupporting at least the inner flange (49) as it slides back and forthovertop the cylinder (8).

In some embodiments, one or more compression springs (55), coupled at afirst end to the cylinder flange (57) and at a second end to the innerflange (49), may be configured to bias the inner flange (49) in anextended position, wherein the holes (51) are disaligned with the holes(52), as long as pressure within said cylinder is not less thanatmospheric pressure, or more generally, when pressure within the outputcylinder is not less than a predetermined amount relative to pressureoutside the output cylinder.

When the inner flange is in an extended position, an endwall of theinner flange sits in a spaced-apart configuration with an end of thecylinder (8). When pressure within said cylinder falls below ambientpressure outside the cylinder, the pressure differential results in aforce against the inner flange, tending to compress the volume withinthe cylinder. The force may overcome the biasing force of saidcompression spring, thereby causing the inner flange to slide into theretracted position, thereby aligning holes (51) and holes (52) to form achannel, facilitating free flow of air or other fluid into outputcylinder during a return stroke of the piston (10) within the cylinder(8). In some embodiments, the compression springs (55) are configured tobias the inner flange (49) in the extended position as long as pressurein the ambient fluid is not greater than pressure in the cylinder (8) bya predetermined amount.

In some embodiments, the external flange (50) may be connected by one ormore extension springs (56) to the inner flange (49). The externalflange (50) comprises a port (53) for facilitating passage of fluid,under compression action of the piston (10) during a power stroke, to areservoir (not shown) operatively coupled thereto via a channel, such asa hose or pipe. The extension springs (56) are configured to bias theexternal flange (50) to contact the inner flange (49), in a retractedposition, as long as pressure in the cylinder (8) is not greater thanpressure in the reservoir and/or channel by a predetermined amount, or,more generally, to bias the outer flange into the retracted positionthereof when pressure within a channel configured to receive fluidoutput from the output cylinder exceeds a predetermined amount relativeto pressure within the output cylinder. The end holes (54) of the innerflange (49) are blocked by a portion of the external flange (50) whensaid external flange is in a retracted position.

For example, the extension springs (56) may be configured to have abiasing force of a predetermined magnitude, which is set against anopposing force due to fluid pressure differential between the outputcylinder (8) interior and the reservoir and/or channel connected to theport (53). When pressure within the output cylinder (8) exceeds pressurein the reservoir and/or channel, the difference in pressure causes thespring biasing force to be overcome, thereby causing the external flange(50) to slide forward overtop the inner flange (49) into a spaced-apartconfiguration, thereby allowing passage of compressed air into a cavityof the external flange through end holes (54) formed in the innerflange. The compressed air then passes through the end holes (54) andport (53) and thence to reservoir and/or channel. On the return strokeof output piston (10), when pressure within output cylinder is less thanor equal to pressure in reservoir, the springs (56) connecting theexternal flange to the inner flange cause said external flange toretract, thereby sealing the end holes (54), and substantiallypreventing backflow of compressed air from the reservoir to the outputcylinder.

In embodiments of the present invention, the bidirectional integratedcheckvalve illustrated in FIG. 3 may facilitate the near-total expulsionof the contents of said output cylinder during a power stroke, comparedto traditional check valves, resulting in increased efficiency.

In some embodiments, an input check valve, comprising the inner flange(49) slidingly engaged over the cylinder (8) may be provided. In someembodiments, an output check valve, comprising the external flange (50)slidingly engaged over the cylinder may be provided. The input andoutput check valves may be provided separately of each other in someembodiments.

In some embodiments, the output cylinder-piston assembly comprises a rodend (11) formed with a shaft (12), the shaft operatively coupled to thepiston base (14), for example by a threading about the shaft engagedwith a corresponding threaded cavity of the piston base (14), and therod end (11) operatively coupled to the output piston (10). The rod end(11) is fitted within a cavity formed within the piston (10), such thatangle between the piston and the shaft (12) can tolerate a predeterminedamount of alignment error, for example between the input piston-cylinderassembly and the output piston-cylinder assembly. Rotational motion maycomprise at least a few degrees of rotation about one or more axes. Therod end (11) may thereby facilitate reduced friction and/or wear duringoperation of the compressor.

As illustrated in FIG. 1, each output cylinder may lie on an axis ofsymmetry running through the center thereof. In some embodiments, theaxes of the piston-cylinder assemblies are offset from the axis of thecrankshaft, such that when one piston reaches the end of its stroke, theother has already passed the end of its stroke and is thus in positionto move when pressurized gas is introduced into the cylinder. Asillustrated in FIG. 19, in some embodiments, the use of an offsetbetween the axes of the piston-cylinder assemblies and the axis of thecrankshaft has the effect that, when piston 1 (1910) of cylinder 1(1915) is at the end of its power stroke, piston 2 (1920) of cylinder 2(1925) has not yet reached the end of its power stroke and is thus stillable to provide moment F (1935) to the crankshaft (1930), therebyeliminating the “dead point” that could otherwise occur should themachines motion be stopped, due to interruption in the supply ofpressurized gas or another reason, precisely when the two pistons are atthe end of their respective strokes.

In some embodiments, for example with respect to the compressor asillustrated in FIG. 1, the transfer system, which is configured totransfer force generated in the input piston-cylinder assemblies ontothe output pistons, comprises a series of rods (15) rigidly coupledbetween the input and output pistons, as illustrated in in FIG. 1. Inother embodiments, the transfer system may also comprise transfer rods,gear systems, drive belts, drive shafts, crankshafts, or the like.

Return System

In embodiments of the present invention, the return of each piston toits original position following its power stroke is carried out at leastin part by a crankshaft assembly (16), to which plural piston-cylinderassemblies are attached by rod-ends. For example, as illustrated in FIG.1, the crankshaft assembly (16) is coupled both to the left input pistonand the right input piston. The left input piston may be configured toexecute at least a part of its power stroke substantially during thesame time that the right input piston executes at least a part of itsreturn stroke, and vice-versa. Force from the power stroke of a pistonmay be transferred to cause rotation of the crankshaft assembly (16),which may in turn be transferred to apply force to execute or assist inexecuting the return stroke of another piston.

In some embodiments, the return system may further comprise otherelements, such as one or more flywheels (59) operatively coupled to thecrankshaft (17), or two or more crankshafts operatively coupled, forexample by one or more drive belts or chains, or the like. The returnsystem may additionally use other mechanical means to facilitate thereturn stroke of one or more pistons.

Timing System

The relative timing of motion of the cylinders and of the distributionsystem is controlled by a timing system, comprising a crankshaftassembly (16) and a gearbox (1), as illustrated in FIG. 4. Pressurizedgas is distributed to each input cylinder and spent gas and/orcondensate fluid is evacuated therefrom by a distribution system, forexample as illustrated in detail in FIG. 5 in accordance with anembodiment of the present invention. The timing system may be configuredto provide feedback about position of the input pistons, which may beused to time operation of the distribution system appropriately, forexample by opening a communicating channel between a source ofpressurized working fluid and an interior cavity of an input cylinder(19) when an input piston (18) thereof is at or near the beginning of apower stroke, and by opening a communicating channel between an interiorcavity of an input cylinder (19) and an exhaust system, reservoir orambient environment, or the like, when an input piston (18) thereof isat or near the beginning of a return stroke.

In some embodiments, the timing system comprises a crankshaft (17),which is situated within the frame (51), and driven, by cranking motion,by linking rods (30 and 31) connected to the input pistons. One or moreflywheels (59), as illustrated in FIG. 1, may be mounted on one or moreends of the crankshaft (29). In some embodiments, said linking rods,connected to the crankshaft (17) and to the input piston (18) by rodends (55), may be fully contained throughout their range of motionwithin a cavity of the compressor, for example within a cavity of theinput cylinder (19) and the spacer (13). For example, the crankshaftassembly (16) may thereby be configured to move inside the inputcylinder (19) and the spacer (13), between the transfer rods (15). Thisarrangement may facilitate the stroke of the output piston beingsubstantially equal to that of the input piston, even if its diameter issmaller.

In some embodiments, the timing system may comprise one or more sensors,such as position sensors, and/or actuators, such as electricallycontrolled valves, communicatively coupled by electrical, mechanical oroptical signals, or the like. For example, a sensor, such as anelectromechanical, optical, or other sensor, may be configured to sensethe rotational position of a crankshaft of the compressor, or an elementcoupled thereto, such as a flywheel. The sensor may further beconfigured to provide a signal based thereon, and an electricallycontrolled valve, actuated by said signal, may be configured to operatebased on said signal. For example, an electrically controlled valve maybe configured to open when a sensor communicatively coupled theretosenses the crankshaft in a first range of rotational positions, and toclose when the sensor senses the crankshaft in a second range ofrotational positions.

In accordance with the above, the timing system may be actuated directlyor indirectly in accordance with rotational position of the crankshaft.The timing system co-operates with the distribution system to facilitateoperation of the compressor. The co-operation of timing and distributionsystem is described further below.

Distribution System

The distribution system, for example illustrated in FIGS. 5, 6 and 7 inaccordance with embodiments of the present invention, is configured tofacilitate circulation of pressurized gas to and from the inputcylinders, in conjunction with the timing system. As the pistonstraverse their strokes, the crankshaft (17) of the timing system iscorrespondingly rotated between a plurality of angular positions, bycranking action of the linking rods (30 and 31). A first gear (2),operatively coupled to the crankshaft (17), and a second gear (3),engaged with the first gear (2), are also correspondingly rotatedbetween a plurality of angular positions. The second gear (3) isoperatively coupled to a valve assembly (23), which is configured tooperate by rotating action to alternatingly establish a firstcommunicating channel between the interior of each input cylinder (19)and a source of pressurized gas, such as vaporized working fluid, and asecond communicating channel between the interior of each input cylinder(19) and an exhaust system (not shown) for receiving spent gas. In someembodiments, a separate valve assembly (23) may be provided for eachcylinder-piston assembly. Plural valve assemblies may be driven by thesame gear or by separate gears.

For example, in some embodiments, the pistons operate substantially outof phase, such that, in a first position, a first piston reaches the endof a power stroke substantially when a second piston reaches the end ofa return stroke, and in a second position, the first piston reaches theend of a return stroke substantially when the second piston reaches theend of a power stroke. The first position corresponds to first angularpositions of the crankshaft, first and second gears, and the valveassembly. The second position corresponds to second angular positions ofthe crankshaft, first and second gears, and the valve assembly. In someembodiments, plural pistons may operate in phase, out of phase, or acombination thereof.

In some embodiments, when rotated by the crankshaft and gears into thefirst angular position, the valve assembly (23) is configured to seal apassage connecting the first cylinder (19) to the source of pressurizedgas and to concurrently open a passage connecting it to the low-pressureoutlet, through a mechanism described into detail below. In someembodiments, at substantially the same time, the distribution system isconfigured to seal a passage connecting the second cylinder to thelow-pressure outlet and to open a passage connecting the second cylinderto the pressurized gas source, thereby facilitating initiation of apower stroke of the second piston.

The crankshaft (17) is configured to drive one of the two substantiallyidentical gears (2) in the gear box (1); wherein the other gear (3)drives the distribution system, which comprises a rotating valve body(36) and a valve body housing (42), illustrated in FIG. 5 with the valvebody (36) retracted from the valve body housing (42). For operation, thevalve body (36) is inserted into the valve body housing (42), such thatthe partial disk (35) is substantially positioned between thehigh-pressure input port (33) and the low-pressure output port (38).

As illustrated in FIG. 5, the valve body (36) comprises a shaft (37),operatively coupled to and turned by the driven gear (3) of the gearbox, a cover (510) connected to the shaft and configured to fit withinan opening of the valve body housing (42) so as to substantially coversaid opening, a partial disk (35) connected to the shaft (37) andconfigured to fit within the valve body housing (42), and a disk-shapedvalve cover (41) with a partial cut-out on its face. The partial disk issituated with the cover (510) along or near a first face thereof, andthe valve cover (41) along or near a second face thereof, opposite thefirst face. The partial disk (35) does not fill the cylindrical regionbetween the cover (58) and the valve cover (41), but rather defines agap (43), the gap communicating with the partial cut-out of the valvecover (41) to form a channel. Gas may flow through said channel when thegap (43) in the partial disk is exposed to the high-pressure (input)port (33) or low-pressure (output) port (38) by rotation of the valvebody (36) by action of the driven gear (3).

The valve body (36) rotates within the valve body housing (42), with asubstantially hermetic seal created by a substantially C-shaped seal(39) formed around the partial disk (35), the seal (39) made of alow-friction material, which is pressed out against the valve bodyhousing by two O-rings (40). The substantially C-shaped seal (39)includes a gap which is substantially aligned with the gap (43). Thepartial disk (35) and C-shaped seal (39) are configured to alternatinglyblock and seal, due to rotation thereof in the valve body housing (42),the high-pressure input port (33) and the low-pressure output port (38).

The valve body housing includes an input port (33) coupled to a sourceof pressurized gas, and an output port (38) coupled to an exhaustsystem, such as ambient atmosphere, a low-pressure reservoir, arecirculation system, a condenser, or the like. The valve body housingalso includes a cylinder port (32) connected by tubing or piping to forma channel to the interior of an input cylinder (19), for example via aninput port (21) as illustrated in FIG. 1.

FIG. 6 illustrates the valve body (42) in further detail with input port(33) and output port (38) coupled thereto, along with the valve cover(41) when the valve body is inserted into the valve body housing (42).

When the partial disk (35) and C-shaped seal (39) are rotated to coveran opening of the input port (33), the input port (33) is sealed fromthe cylinder port (32). In some embodiments, said partial disk and sealmay be configured such as to cut off supply of pressurized gas to theinput cylinder before the input piston has completed its stroke, therebyallowing the pressurized gas already present within said cylinder todilate by further displacing the piston. This configuration allows formore efficient operation, in that a greater percentage of the potentialenergy contained in the pressurized gas is converted to useful work.

In some embodiments, the hermetic nature of this seal may be improved bythe addition of a secondary sealing assembly as illustrated in FIG. 7.This secondary seal assembly comprises a threaded hollow housing (44)that forms part of a channel of the input port (33) and that attaches,for example by screwing, into an opening of the valve body (36) at thelocation of the input port (33), a hollow threaded inner valve shaft(45) with a bonded end (46) that may be attached into the housing (44),for example by screwing, the bonded end (46) contacting the interiorwall of the housing (44). The bonded end (46) may in some embodiments becomposed of a flexible, heat-resistant material such as silicone. Thehollow housing (44) thereby provides a recess that forms part of achannel of the input port, and the bonded end (46) provides an end pieceformed within the recess. The secondary seal assembly further comprisesa sealing disk (47) configured to fit within an opening of the housing(44), the sealing disk (47) movable along a longitudinal axis of thehousing (44) between an open position and a closed position, the openposition corresponding to the sealing disk (47) being in a spaced-apartconfiguration with the bonded end (46), and the closed positioncorresponding to the sealing disk (47) contacting the bonded end (46).

A guide assembly (48) is attached to the sealing disk (47), which may beconfigured to constrain motion thereof between the open position and theclosed position. The guide assembly (48) may further include aprotruding portion which is formed overtop of the sealing disk (47), andwhich may be conically or frustro-conically shaped, or otherwise beconfigured with one or more sloped or ramped edges.

The sealing disk (47) includes one or more channels or holes therein toestablish a communicating channel between the input port (33) and thecavity of the valve body housing (42), to thereby permit passage of thepressurized gas when the sealing disk (47) is in the open position. Apressure differential between the source of pressurized gas in the inputport (33) and the cavity of the valve body housing (42) may bias thesealing disk (47) toward the open position. A spring or other biasingmeans may also be used to bias the sealing disk (47) into the openposition, in addition or alternatively to biasing resulting from thepressure differential.

Continuing with respect to the secondary sealing assembly illustrated inFIG. 7, whenever the partial disk (35) and the C-shaped seal (39) arerotated so as to lie overtop of the input port (33), the C-shaped seal(39) pushes on the protruding portion of the guide assembly (48),thereby forcing it into the closed position, such that the sealing disk(47) contacts against the bonded end (46) of the inner valve shaft (45),thereby covering the holes of the sealing disk (47) and substantiallyinhibiting flow of the pressurized gas. The sloped or ramped edge shapeof the protruding portion facilitates pushing of the sealing disk (47)into the closed position, by allowing the C-shaped seal (39) togradually displace the protruding portion out of the cavity of the valvebody housing.

According to embodiments of the present invention, a similar valvesystem allows the expulsion of pressurized gas when the input piston(18) is returned to its initial position by the timing assembly.

According to some embodiments of the present invention, a quick-exhaustvalve (not shown) is affixed to the input cylinder head (22), in orderto allow for a more rapid expulsion of said pressurized gas. Saidquick-exhaust valve may be controlled by a solenoid, controlled by anelectrical signal produced by a switch triggered mechanically oroptically according to the position of the flywheel (59), or by anothermeans. Alternatively, it may be controlled by a hydraulic valve (notshown) triggered by the presence of pressurized gas in the other inputcylinder (19).

According to some embodiments of the present invention, a mechanicallyor electrically controlled input valve affixed directly or by means of aport to the input cylinder head may replace the rotational valveillustrated in FIGS. 5 to 7. Said valve may be controlled by a solenoid,controlled by an electrical signal produced by a switch triggeredmechanically or optically according to the position of the flywheel(59), or by another means. Alternatively, it may be controlled by ahydraulic valve (not shown) triggered by the presence of pressurized gasin the other input cylinder (19).

According to embodiments of the present invention, the cylinders,pistons and structural elements are fabricated from steel or fromstainless steel, the O-rings from silicone, the cylindrical piston rings(28) from vitrified PTFE and the C-shaped seal (39) from Vespel or asimilar material. Alternate materials for each of the components ofwould be readily understood by a worker skilled in the art.

In accordance with an embodiment of the present invention, the geometryof the compressor is further configured or aligned to ensure that uponinterruption of a supply of pressurized gas, one of the inputpiston-cylinder assemblies is always in active position, such that thereis no “dead point”, regardless of the position at the moment ofinterruption of the supply of pressurized gas.

In accordance with an embodiment of the present invention, two or moretwo-cylinder assemblies, such as the one illustrated in FIG. 1, can bejoined together in an assembly comprising four (4) or more inputcylinders and a similar or different number of output cylinders. Forexample, in one such embodiment, as illustrated in FIG. 18, twotwo-cylinder assemblies (1800 and 1810) such as those illustrated inFIG. 1 could be joined together, with their flywheels (1805 and 1815)connected by a chain or belt (1830). In this embodiment, the timing ofone two-cylinder assembly (1800) is set so as to be 90° out of phasefrom the timing of the other two-cylinder assembly (1810), such that,when the pistons in the first two-cylinder assembly (1800) are at ornear the ends of their respective strokes, the pistons of the secondtwo-cylinder assembly (1810) are approximately in the middle of theirrespective strokes. The result is to smooth out the variations in forceapplied that otherwise would occur when the pistons reach the ends oftheir respective strokes, and to reduce potential occurrence of a “deadpoint” at the end of said strokes. A pressurized-gas powered compressorin accordance with the present invention may thereby comprise a firstpair of two or more input piston-cylinder assemblies and a second pairof two or more input piston-cylinder assemblies, and wherein the timingsystem is configured to operate the first pair of two or more inputpiston-cylinder assemblies out of phase with the second pair of two ormore input piston-cylinder assemblies.

In accordance with other embodiments of the present invention, thenumber of input and output cylinders may be different from each other.For example, additional input cylinders could be added in order toprovide additional torque to the crankshaft, whether to provide motiveforce directly via said crankshaft, or to provide additional compressiveforce to the output pistons.

System

In accordance with an aspect of the present invention, there is provideda system for extracting work using a pressurized gas powered compressor.The system generally comprises a pressurized gas input system, apressurized gas powered compressor, powered by the pressurized gas inputsystem, an exhaust system operatively coupled to the pressurized gaspowered compressor and configured to convey spent gas and/or condensatetherefrom, and a work extraction system operatively coupled to thepressurized gas powered compressor and configured to extract worktherefrom.

FIG. 8 illustrates a system (800) for extracting work using apressurized gas powered compressor, in accordance with embodiments ofthe present invention. The system comprises a pressurized gas inputsystem (810) configured as a source of pressurized gas, such assaturated steam or vapour generated from a low boiling point (LBP)working fluid, a pressurized gas powered compressor (830) powered by thepressurized gas from the pressurized gas input system (810), an exhaustsystem (850) for conveying spent gas and/or condensate from thepressurized gas powered compressor (830) after use, and a workextraction system (870), powered by the pressurized gas poweredcompressor (830) and configured to store or convey energy in one or moreforms.

The pressurized gas input system (810) may be configured to generatepressurized gas using heat energy (815) from one or more sources, suchas solar, fuel combustion, heat from an industrial process, or the like.In some embodiments, the work extraction system (870) comprises one ormore check valves (875) and one or more devices (880) such asaccumulators, reservoirs, motors, generators, or the like.

The pressurized gas input system is configured to utilize heat from aheat source to create pressurized gas from a working fluid or workingfluid condensate, such as water or liquid LBP working fluid. In someembodiments, a heat exchanger is used to transfer heat from the heatsource to the working fluid. Potential LBP working fluids may includen-pentane, toluene, and ammonia, for example, or other fluids, ormixtures thereof, or aqueous or non-aqueous solutions thereof. Thepressurized gas is created in a boiler, vapour generator, or similarapparatus, and conveyed under pressure to an input of the pressurizedgas powered compressor.

According to embodiments of the present invention, the heat source maycomprise a solar concentrator, a biomass combustion apparatus, a sourceof heat such as waste heat from one or more industrial processes, or acombination thereof, or the like.

According to embodiments of the present invention, the compressor isconfigured to be driven by steam or other pressurized gas generated byone or more devices or mechanisms that concentrate heat from solarradiation and/or that produce heat from the combustion of biomass orother fuels, in order to produce electricity from renewable sources.

For example, FIG. 9A illustrates a configuration for driving apressurized gas powered compressor (910) using residual steam, inaccordance with an embodiment of the present invention. The residualsteam is provided as partially spent gas output by an industrial process(920), which utilizes high-pressure steam from a boiler (930).

As another example, FIG. 9B illustrates a configuration for driving apressurized gas powered compressor (910) using steam generated in aboiler (940) using a heat source, in accordance with an embodiment ofthe present invention. The steam may be wet saturated steam. The heatsource may a heat exchanger (950) configured to convey heat from anindustrial heat source (955), a biomass combustion device (960), a solarconcentrator, or other heat source, or a combination thereof. FIGS. 9Aand 9B further illustrates a condenser (935) for condensing exhaustedsteam, and a pump (937) for facilitating recirculation of hot exhaustwater back to the boiler (930).

According to some embodiments of the present invention, the gas inputsystem may be configured to provide pressurized gas to a plurality ofapparatuses, including the pressurized gas powered compressor, forexample in series or in parallel. For example, in some embodiments thepressurized gas input system is configured to provide pressurized gas tothe pressurized gas powered compressor after said pressurized gas isused for one or more other processes. For example, the one or moreprocesses may be industrial processes, machinery operating processes,heating or cooling processes, or the like. The pressurized gas outputfrom the one or more other processes, which may be considered spent gasin the context of said processes, may nonetheless still containsufficient energy for operation of the pressurized gas poweredcompressor. In some embodiments of the present invention, a pressurizedgas powered compressor may be advantageously operated using wet orpartially spent or other working fluid.

According to some embodiments, the exhaust system is configured torecirculate working fluid, for example spent gas and/or condensate, tothe gas input system. The exhaust system may cool the working fluid tofacilitate flow of the spent gas from the gas powered compressor. Insome embodiments, the exhaust system may utilize the working fluid forfurther processes, such as heating, cooling, adsorption chilling,absorption chilling, or the like. In some embodiments, the exhaustsystem does not recirculate working fluid, but may instead expel theworking fluid, such as spent gas, steam, condensate, water, or the like,from the system. The gas input system and exhaust system may becollectively configured to generate a gradient, such as a pressureand/or thermal gradient, between an input and an output of thepressurized gas powered compressor, which biases working fluid to flowthrough the pressurized gas powered compressor from the gas input systemto the exhaust system.

In some embodiments, working fluid for converting to pressurized gas,for example in a boiler or vapour generator, may be provided from anexternal source of fresh or make-up fluid, as recirculated fluid fromthe exhaust system (850), or a combination thereof. For example,condensed working fluid from the exhaust system (850) may be provided toa boiler or vapour generator for re-conversion into gas, since it isalready substantially preheated, and makeup fluid may be provided froman external source to compensate for working fluid losses as the workingfluid circulates. In some embodiments, the makeup fluid may bepreheated, for example via a heat exchanger which is configured totransfer heat from the exhaust system (850), for example from acondenser thereof, to the makeup fluid.

The pressurized gas powered compressor generally comprises an inputcircuit operatively coupled to the pressurized gas input system and theexhaust system, and an output circuit operatively coupled to the workextraction system. The pressurized gas is configured to flow through theinput circuit and to perform work thereon, for example by moving pistonsof the input circuit. The pressurized gas powered compressor furthercomprises a transfer system configured to transfer work from the inputcircuit to the output circuit, for example by transferring force frommoving pistons of the input circuit to move pistons of the outputcircuit, for example using transfer rods, gear systems, drive belts,drive shafts, crankshafts, or the like. The pressurized gas poweredcompressor further comprises additional elements, such as a timingsystem, distribution system, and/or valve gear system, configured tocontrol and/or facilitate the flow of pressurized gas and exhaustthrough the input circuit.

According to embodiments of the present invention, a system forextracting work using a pressurized gas powered compressor may comprisea pressurized gas powered compressor substantially as described indetail herein, for example with respect to FIG. 1. According toembodiments of the present invention, a system for extracting work usinga pressurized gas powered compressor may comprise other configurationsof pressurized gas powered compressors, which, in some embodiments, maybe referred to as reciprocating pumps, steam pumps, pumping engines, orthe like.

For example, in some embodiments, a system for extracting work using apressurized gas powered compressor may generally comprise a pressurizedgas powered compressor comprising an output circuit configured tooperate compressively on an output fluid supplied thereto, which isutilized for performing work, transferring force, storing energy, or thelike, in a work extraction system, the pressurized gas poweredcompressor powered by gas from a pressurized gas input system.

For example, the pressurized gas powered compressor comprises one, twoor more input piston-cylinder assemblies and one, two or more outputpiston-cylinder assemblies operatively coupled to each of the inputpiston-cylinder assemblies. In some embodiments, the compressor may havea simplex configuration, with an output piston-cylinder assemblyoperatively coupled to an input piston-cylinder assembly at one endthereof. In some embodiments, the compressor may have a duplexconfiguration, with output piston-cylinder assemblies operativelycoupled to an input piston-cylinder assembly at both ends thereof.

In some embodiments, an input piston-cylinder assembly may besingle-acting, with compressed gas applied in the cylinder to operatethe piston during the power stroke only. In some embodiments, an inputpiston-cylinder assembly may be double-acting, with compressed gasapplied in the cylinder to operate the piston during both the powerstroke and the return stroke, for example by applying compressed gasalternatingly to either side of the piston, as would be readilyunderstood by a worker skilled in the art.

In some embodiments, an output piston-cylinder assembly may besingle-acting, with fluid pumped thereby during the power stroke only.In some embodiments, an output piston-cylinder assembly may bedouble-acting, with fluid compressed and/or pumped thereby during boththe power stroke and the return stroke, for example by pumping fluidalternatingly from cavities on either side of the output piston, aswould be readily understood by a worker skilled in the art.

In some embodiments, two or more single-acting input piston-cylinderassemblies may be operated in phase, such that the two or more pistonsexecute power strokes and return strokes substantially concurrently, outof phase, such that one of the two or more pistons executes a powerstroke as another executes a return stroke, or a combination thereof.

In some embodiments, two or more input piston-cylinder assemblies may bearranged in a cascading configuration, such that pressurized gaspartially exhausted by a first input piston-cylinder assembly is provideas input gas to a second input piston-cylinder assembly. In someembodiments, two or more input piston-cylinder assemblies may bearranged in a parallel configuration, such that pressurized gas issupplied from the same source thereto.

The work extraction system is generally configured to transform workperformed by the output circuit into work applied to one or moreapplications, such as electricity generation, water or fluid pumping,air compression, mechanical force applied to an apparatus, or the like.The work extraction system is configured to convey work performed by theoutput circuit via one or more fluids, such as liquids or gases, whereinone of the one or more fluids is moved by compression action of theoutput circuit, for example via cylinders thereof.

In some embodiments, the work extraction system and/or output circuitcomprises one or more valves, such as check valves. The valves may beconfigured to inhibit backflow of a fluid conveyed by the workextraction system, thereby facilitating extraction of useful work.

In some embodiments, the work extraction system comprises an energystorage device such as a hydraulic or hydro-pneumatic accumulator orpressurized tank. The energy storage device may be configured to storeenergy accumulated from work extracted by the work extraction system,for example by holding a non-compressible fluid under pressure, thepressure applied via the extracted work. An accumulator or other energystorage device may operate as a buffer, so that the extracted work neednot be used immediately, but rather may be stored for future use.

In some embodiments, the work extraction system comprises a hydraulic orpneumatic motor operated by a fluid conveyed under pressure by the workextraction system. The hydraulic or pneumatic motor may be operated toperform mechanical work, such as moving objects, operating machinery, orthe like.

In some embodiments, the work extraction system may be configured topump water. For example, pumped water may be drawn into an input port ofthe output circuit and expelled, by compression action out of an outputport of the output circuit and into an output channel. Pumping of watermay be performed to raise the water to a predetermined height and into astorage reservoir. In some embodiments, the storage reservoir may beused to store energy as gravitational potential energy. For example, thewater may be stored at a height from which it may be subsequentlyreleased to drive a hydraulic turbine or used for other purposes. Insome embodiments, the water may be driven by gravity to drive anelectric generator, as would be readily understood by a worker skilledin the art.

In some embodiments, the work extraction system may be configured togenerate electricity. For example, a fluid conveyed, for example underpressure, by the work extraction system may be used to operate anelectric generator by applying force to a turbine operatively coupledthereto, a hydraulic or pneumatic motor operatively coupled thereto, ora combination thereof. In some embodiments, additional controlmechanisms may be implemented in order to follow loads and/or to controlthe quality of the electricity produced.

In some embodiments, the work extraction system comprises a compressedair storage reservoir, and the output circuit is configured to producepressurized air that is stored in said storage reservoir. Thepressurized air may be released in varying amounts in order to turn amotor or turbine which in turn drives a generator, so as to produceelectricity as needed. In some embodiments, this may obviate the needfor an electrical energy storage device. In some embodiments, thepressurized air may be used for other applications, such as foroperating pneumatic tools, or the like.

For example, FIG. 10A illustrates a configuration for producingcompressed air using a pressurized gas powered compressor (1010), inaccordance with an embodiment of the present invention. Air is pumped bythe compressor (1010) via check valves (1015) to a compressed airreservoir (1020).

As another example, FIG. 10B illustrates a configuration for producingmotive force using a pressurized gas powered compressor (1010), inaccordance with an embodiment of the present invention. Pressure of ahydraulic fluid, such as water or oil, is built in a hydraulicaccumulator (1030) by pumping action of the compressor (1010) via checkvalves (1015). In some embodiments, the hydraulic accumulator (1030) mayoperate as a buffer, for example so that the extracted work need not beused immediately, but rather may be stored for future use. Such a buffermay be used to facilitate coping with fluctuations or mismatches betweenenergy supply and energy demand. For example, the compressor (1010) maypump hydraulic fluid into the hydraulic accumulator (1030), or thecompressor (1010) may pump air to fill an expandable bladder in thehydraulic accumulator (1030), or the like. Pressurized hydraulic fluidin the hydraulic accumulator (1030) may be used to operate a hydraulicmotor (1040) for producing motive force.

As yet another example, FIG. 10C illustrates a configuration forproducing electricity using a pressurized gas powered compressor (1010),in accordance with an embodiment of the present invention. Pressure of ahydraulic fluid, such as water or oil, is built in a hydraulicaccumulator (1030), which may operate as an energy buffer, by pumpingaction of the compressor (1010) via check valves (1015). Pressurizedhydraulic fluid in the hydraulic accumulator (1030) may be used tooperate a hydraulic motor (1050), which is operatively coupled to anelectric generator (1060). Force applied to the electric generator(1060) results in generated electricity, which may be transmitted orstored for future use. In some embodiments, the hydraulic motor (1050)and electric generator (1060) may be integrated as a hydraulic generatormachine.

According to embodiments of the present invention, the pressurized gasinput system is configured to supply the input circuit of thepressurized gas powered compressor with low or medium pressure saturatedsteam, and the output circuit of the pressurized gas powered compressoris supplied with ambient air, which operates as a fluid conveyed by thework extraction system. In these embodiments, the system can beconfigured to deliver compressed air to an industrial compressed airsystem, thereby replacing the electricity which would typicallyotherwise have been used by the air compressors.

According to embodiments of the present invention, the input circuit issupplied with low or medium pressure saturated steam, and the outputcircuit is joined to a hydraulic circuit. In these embodiments, thepressurized gas powered compressor may be configured to deliver a flowof pressurized hydraulic fluid, which can be configured to drive ahydraulic motor, which may in turn drive an electric generator.

According to embodiments of the present invention, the input circuit issupplied with low or medium pressure saturated steam, and the outputcircuit is supplied with water or another fluid. In these embodiments,the compressor delivers a flow of said liquid which can be used eitherfor projecting it against a wheel, turbine or turbine-generator tocreate rotational force, for displacing said liquid (pumping), or fordisplacing it to a higher elevation in order to store potential energyfor subsequent release through a wheel, turbine or turbine-generator.

The invention will now be described with reference to specific examples.It will be understood that the following examples are intended todescribe embodiments of the invention and are not intended to limit theinvention in any way.

EXAMPLES

FIG. 11 illustrates a system for extracting electricity from solarenergy using a pressurized gas powered compressor (1130), in accordancewith an embodiment of the present invention. The system comprises asolar concentrator (1110) configured to convey heat energy from the sunto a vapour generator (1120). The vapour generator (1120) utilizes theheat energy for boiling a LBP working fluid into a pressurized vapour.The pressurized vapour is provided as input to an input circuit of thepressurized gas powered compressor (1130) and performs work thereon. Thespent vapour is exhausted from the pressurized gas powered compressor(1130) to an exhaust system and condensed in condenser (1140), beforebeing recirculated back to the vapour generator (1120) for reboiling.Recirculation of liquid working fluid from the condenser (1140) maycomprise pumping using a pump (1145).

The gas powered compressor (1130) conveys power from its input circuitto an output circuit thereof, which is configured to compressivelyperform work on a hydraulic fluid, such as oil or water, for example bypumping it. The output circuit of the gas powered compressor (1130) isoperatively coupled to a work extraction system which comprises checkvalves (1150), a hydraulic accumulator (1160), a hydraulic motor (1170),and an electric generator (1180). Fluid is pumped under pressure fromthe output circuit through the check valves (1150) and into thehydraulic accumulator (1160), which may store hydraulic fluid underpressure, gravitational potential energy, or a combination thereof, orthe like. The hydraulic fluid may subsequently be channelled to driveone or more hydraulic motors (1170), such as a rotary motor configuredto convert hydraulic pressure and flow into mechanical torque andangular displacement of the motor. For example, the hydraulic motor(1170) may be a gear and vane motor, axial plunger motor, radial pistonmotor, or the like. In some embodiments, the hydraulic motor may beconfigured to drive an electric generator to generate electricitydirectly due to rotational motion thereof. In some embodiments, anelectric generator (1180) may be operatively coupled to the hydraulicmotor (1170), for example via gear systems, drive shafts, drive belts,or a combination thereof, or the like, the electric generator configuredto generate electricity from mechanical motion thereof. The electricitymay be stored, used for one or more applications, transferred to a powertransmission or power distribution system, or the like, or a combinationthereof. In some embodiments, additional control mechanisms may beimplemented in order to follow loads and/or to control the quality ofthe electricity produced.

FIG. 12 illustrates a system for extracting electricity from biomasscombustion using a pressurized gas powered compressor, in accordancewith an embodiment of the present invention. The system may operatesubstantially similarly to the system described with respect to FIG. 11,except that, instead of a solar concentrator, the system comprises abiomass combustion apparatus (1210) configured to generate heat energyfrom combustion of biomass fuel, such as wood products, plant products,animal products, or a combination thereof, or the like, the heat energyconveyed to a vapour generator. Additionally, in some embodiments, theworking fluid may be water and/or steam instead of a LBP working fluid.The system may comprise a boiler (1220) for boiling steam using heatfrom the biomass combustion apparatus (1210), a compressor (1230)operated by steam from the boiler (1220), a condenser (1240) forcondensing exhaust steam from the compressor (1230) and a pump (1245)for recirculation of condensed exhaust. The system may further compriseone or more check valves (1250) operatively coupled to an output circuitof the compressor (1230), along with a hydraulic accumulator (1260),hydraulic motor (1270), and electric generator (1280) of a workextraction system, configured for generation of electricity usinghydraulic fluid from the compressor (1230).

FIG. 13 illustrates a system for extracting electricity from solarenergy, biomass combustion, or a combination thereof, using apressurized gas powered compressor, in accordance with an embodiment ofthe present invention. The system may operate substantially similarly tothe systems described with respect to FIGS. 11 and 12, except that oneor more of a plurality of heat sources may be selectably used. Heatenergy may be generated substantially concurrently or at different timesby a solar concentrator (1310) and a biomass combustion apparatus(1315). Use of a plural heat sources may increase reliability, economicviability, or the like, of the system. The system may comprise a vapourgenerator (1320) for generating high-pressure vapour using heat from thebiomass combustion apparatus (1315) and/or solar concentrator (1310), acompressor (1330) operated by vapour from the vapour generator (1320), acondenser (1340) for condensing exhaust from the compressor (1330) and apump (1345) for recirculation of condensed exhaust. The system mayfurther comprise one or more check valves (1350) operatively coupled toan output circuit of the compressor (1330), along with a hydraulicaccumulator (1360), hydraulic motor (1370), and electric generator(1380) of a work extraction system, configured for generation ofelectricity using hydraulic fluid from the compressor (1330).

FIG. 14 illustrates a system for extracting electricity from anindustrial heat source (1405) using a pressurized gas poweredcompressor, in accordance with an embodiment of the present invention.The system may operate substantially similarly to the systems describedwith respect to FIG. 11 or 12, except that heat energy provided to theboiler is generated from an industrial process, and may be passedthrough a heat exchanger (1410). For example, industrial processes mayinclude smelting processes, chemical processes involving exothermicreactions, processes using heated solids, liquids, or gases which aresubsequently cooled, for example via the heat exchanger (1410), or thelike. In some embodiments, the system is configured to utilize wasteindustrial heat for electricity generation. The system may comprise aboiler (1420) for boiling steam using heat from the biomass combustionapparatus (1410), a compressor (1430) operated by steam from the boiler(1420), a condenser (1440) for condensing exhaust steam from thecompressor (1430) and a pump (1445) for recirculation of condensedexhaust. The system may further comprise one or more check valves (1450)operatively coupled to an output circuit of the compressor (1430), alongwith a hydraulic accumulator (1460), hydraulic motor (1470), andelectric generator (1480) of a work extraction system, configured forgeneration of electricity using hydraulic fluid from the compressor(1430).

Alternatively, in accordance with an embodiment of the present inventionas illustrated in FIG. 15, the system may be configured for extractingmotive force from an industrial heat source using a pressurized gaspowered compressor. For example, a hydraulic motor (1570) may beconfigured to provide mechanical motive force for use in one or moreappropriate applications, such as for operating tools or machinery, aswould be readily understood by a worker skilled in the art, instead ofor in addition to generation of electricity. The system may comprise aboiler (1520) for boiling steam using heat from the heat exchanger(1510), a compressor (1530) operated by steam from the boiler (1520), acondenser (1540) for condensing exhaust steam from the compressor (1530)and a pump (1545) for recirculation of condensed exhaust. The system mayfurther comprise one or more check valves (1550) operatively coupled toan output circuit of the compressor (1530), along with a hydraulicaccumulator (1560), and the hydraulic motor (1570), of a work extractionsystem configured for generation motive force.

FIG. 16 illustrates a system for producing compressed air from residualsteam using a pressurized gas powered compressor, in accordance with anembodiment of the present invention. A boiler (1610), fuelled forexample by industrial heat, solar energy, biomass combustion, fossilfuel combustion, or the like, high-pressure steam, which may besuperheated steam, from the boiler is partially used in an industrialprocess (1620). The residual steam from the industrial process, whichmay be wet or saturated steam, is provided as input to an input circuitof the pressurized gas powered compressor (1630) and performs workthereon. The spent working fluid is exhausted from the pressurized gaspowered compressor (1630) to an exhaust system and condensed incondenser (1640), before being recirculated back to the boiler (1610)for reboiling. The gas powered compressor (1630) conveys power from itsinput circuit to an output circuit thereof, which is configured tocompressively perform work on a compressible fluid, such as air, bypumping it. The air is pumped through one-way check valves (1650) to acompressed air reservoir (1660), where it may be stored and subsequentlyused for applications such as for operating pneumatic tools ormachinery, or for transferring to portable containers, or the like.

FIG. 17 illustrates a system for pumping water using solar energy usinga pressurized gas powered compressor, in accordance with an embodimentof the present invention. The system may operate substantially similarlyto the system described with respect to FIG. 11, except that thehydraulic fluid pumped by the output circuit is water, and a hydraulicaccumulator, hydraulic motor, and electric generator may not berequired. The system may be used, for example, to pump drinking waterfrom a well or aquifer, to pump water to a reservoir, over an obstacle,or the like. The system may comprise a solar concentrator (1710)configured to convey heat energy from the sun to a vapour generator(1720), a compressor (1730) operated by vapour from the vapour generator(1720), a condenser (1740) for condensing exhaust from the compressor(1730) and a pump (1745) for recirculation of condensed exhaust. Thesystem may further comprise one or more check valves (1750) operativelycoupled to an output circuit of the compressor (1730).

It is obvious that the foregoing embodiments of the invention areexamples and can be varied in many ways. Such present or futurevariations are not to be regarded as a departure from the spirit andscope of the invention, and all such modifications as would be obviousto one skilled in the art are intended to be included within the scopeof the following claims.

1. A system for extracting work using a pressurized gas poweredcompressor, the system comprising: a) a compressor powered by apressurized gas, the compressor comprising an output circuit configuredto operate compressively on an output fluid supplied thereto; b) apressurized gas input system configured to provide the pressurized gasfor powering the compressor; c) an exhaust system configured to conveyspent gas from the compressor; and d) a work extraction systemconfigured to extract work from the compressor at least in part via saidoutput fluid.
 2. The system according to claim 1, wherein the compressorcomprises: a) an input circuit configured to channel the pressurized gasthrough two or more input piston-cylinder assemblies, wherein each inputpiston-cylinder assembly is configured to expel spent gas after use; b)an output circuit including two or more output piston-cylinderassemblies, each output piston-cylinder assembly including an intakevalve for entry of fluid and an output valve for exit of compressedfluid; c) a transfer system configured to transfer force generated inthe input piston-cylinder assemblies onto the output piston-cylinderassemblies; d) a return system configured to facilitate a return strokeof at least a first one of the input piston-cylinder assembliesfollowing a power stroke thereof; e) a timing system configured tocontrol input and exhaust of the pressurized gas from the inputpiston-cylinder assemblies; and f) a distribution system operativelycoupled to the timing system, to the pressurized input system, and tothe input circuit, the distribution system configured to cooperativelyprovide pressurized gas to the input piston-cylinder assemblies.
 3. Thesystem according to claim 2, wherein the return system comprises arotating crankshaft actuated by motion of at least one of the inputpiston-cylinder assemblies.
 4. The system according to claim 3, whereinthe timing system is actuated at least in part directly or indirectly inaccordance with rotational position of the rotating crankshaft.
 5. Thesystem according to claim 3, wherein the distribution system comprises arotating valve assembly actuated by the rotating crankshaft, therotating valve assembly configured to provide pressurized gas to one ormore of the input piston-cylinder assemblies according to rotationalposition of the rotating valve assembly.
 6. The system according toclaim 3, wherein the timing system comprises a gearbox which transfersmotion of the crankshaft to the distribution system.
 7. The systemaccording to claim 2, wherein the timing system is actuated by presenceor absence of pressure in at least one of the input piston-cylinderassemblies. 8-19. (canceled)
 20. The system according to claim 1,wherein the system is configured to be driven by steam or anotherpressurized gas generated by one or more devices selected from the groupcomprising: devices that concentrate heat from solar radiation, devicesthat produce heat from the combustion of biomass, and devices theproduce heat from the combustion of other renewable or non-renewablefuels. 21-24. (canceled)
 25. A compressor powered by a pressurized gas,comprising: a) an input circuit configured to channel the pressurizedgas through two or more input piston-cylinder assemblies, wherein eachinput piston-cylinder assembly is configured to expel spent gas afteruse; b) an output circuit including two or more output piston-cylinderassemblies, each output piston-cylinder assembly including an intakevalve for entry of fluid and an output valve for exit of compressedfluid; c) a transfer system configured to transfer force generated inthe input piston-cylinder assemblies onto the output piston-cylinderassemblies; d) a return system configured to facilitate a return strokeof at least a first one of the input piston-cylinder assembliesfollowing a power stroke thereof; e) a timing system configured tocontrol input and exhaust of the pressurized gas from the inputpiston-cylinder assemblies; and f) a distribution system operativelycoupled to the timing system, to the pressurized input system, and tothe input circuit, the distribution system configured to cooperativelyprovide pressurized gas to the input piston-cylinder assemblies.
 26. Thecompressor according to claim 25, wherein the return system comprises arotating crankshaft actuated by motion of at least one of the inputpiston-cylinder assemblies.
 27. The compressor according to claim 26,wherein the timing system is actuated directly or indirectly inaccordance with rotational position of the rotating crankshaft.
 28. Thecompressor according to claim 26, wherein the distribution systemcomprises a rotating valve assembly actuated by the rotating crankshaft,the rotating valve assembly configured to provide pressurized gas to oneor more of the input piston-cylinder assemblies according to rotationalposition of the rotating valve assembly.
 29. The compressor according toclaim 25, wherein axes of two or more of the input piston-cylinderassemblies are offset from an axis of the crankshaft, such that when apiston of a first input piston-cylinder assembly reaches the end of itsstroke, a piston of a second input piston-cylinder assembly has alreadypassed the end of its stroke and is thus in position to move whenpressurized gas is introduced into the cylinder.
 30. The compressoraccording to claim 25, wherein at least one of the input piston-cylinderassemblies and the output piston-cylinder assemblies comprises a pistonfitted with one or more double rings, each double ring comprising anO-ring set into a groove and a machined ring made of a low-frictionmaterial, the O-ring configured to apply outward pressure to themachined ring, thereby providing a hermetic seal between each piston andan associated cylinder wall and reducing need for lubrication.
 31. Thecompressor according to claim 25, wherein the distribution system isconfigured to cut off of supply of pressurized gas to an inputpiston-cylinder assembly before an input piston thereof has completedits stroke, thereby allowing pressurized gas already present within saidcylinder to dilate by further displacing the input piston.
 32. Thecompressor according to claim 25, wherein the distribution systemcomprises: a) a valve body housing comprising: i) an input portconnected to the pressurized gas input system; ii) an output portconnected to the exhaust system; and iii) a cylinder port connected toone or more piston-cylinder assemblies; and b) a rotating valve body,rotatably fitted in the valve body housing, the rotating valve bodyincluding a partial disk fitted with a seal made of a low-frictionmaterial and a valve cover with a partial cut-out on its face; wherein:in a first rotational position of the rotating valve body, a channel isformed between the input port and the cylinder port, and the output portis blocked; and in a second rotational position of the rotating valvebody, a channel is formed between the output port and the cylinder port,and the input port is blocked.
 33. The compressor according to claim 32,wherein the valve body housing further comprises a secondary sealassembly operatively coupled to the input port, the secondary sealingassembly comprising: a) a recess that forms part of a channel of theinput port; b) an end piece formed within the recess, the end piececomprising a flexible material; c) a sealing disk movable along alongitudinal axis of the channel of the input port between an openposition and a closed position, the sealing disk including one or moresecondary channels therein, the sealing disk in a spaced-apartconfiguration with the end piece in the open position therebyfacilitating passage of gas between the cylinder port and the input portwhen in the open position, the sealing disk in contact with the endpiece in the closed position thereby sealing the cylinder port from theinput port when in the closed position; and d) a guide assemblyoperatively coupled to the sealing disk, the guide assembly comprising aprotruding portion, the protruding portion configured to engage with therotating valve body to move the sealing disk into the closed position,and to allow the sealing disk to move into the open position when theprotruding portion is not engaged by the rotating valve body.
 34. Thecompressor according to claim 25, wherein at least one outputpiston-cylinder assembly comprises an integrated intake check valve,said integrated intake check valve comprising: a) an inner flangeslideably coupled a portion of the output piston-cylinder assembly, theinner flange movable between an extended position and a retractedposition, the inner flange having a first set of one or more holestherein, said first set of holes configured to align with a second setof holes formed in the output piston-cylinder assembly when said innerflange is in the retracted position, thereby facilitating filling of theoutput piston-cylinder assembly with fluid; and b) a spring systemconfigured to bias the inner flange into the extended position thereofwhen pressure within the output piston-cylinder assembly exceeds apredetermined amount relative to pressure outside the outputpiston-cylinder assembly.
 35. The compressor according to claim 25,wherein at least one output piston-cylinder assembly comprises anintegrated output check valve, said integrated output check valvecomprising: a) an outer flange, slideably coupled over a portion of theoutput piston-cylinder assembly, the outer flange movable between anextended position and a retracted position, the outer flange configuredto block passage of fluid through one or more end holes when the outerflange is in the retracted position, the outer flange configured tounblock passage of fluid through said one or more end holes when theouter flange is in the extended position, said one or more end holesformed in said portion of the output piston-cylinder assembly, the outerflange further comprising an outlet port; b) a spring system configuredto bias the outer flange into the retracted position thereof whenpressure within a channel configured to receive fluid output from theoutlet port exceeds a predetermined amount relative to pressure withinthe output cylinder.
 36. The compressor according to claim 25, whereinthe input circuit comprises a first pair of two or more inputpiston-cylinder assemblies and a second pair of two or more inputpiston-cylinder assemblies, and wherein the timing system is configuredto operate the first pair of two or more input piston-cylinderassemblies out of phase with the second pair of two or more inputpiston-cylinder assemblies.
 37. (canceled)